"Pete C." wrote

Why on earth would you put a switch halfway when the total run is only
1/2 the max length spec for 100Mbit Ethernet on cat 5 cable (100m)???

For other installations there is this:
http://www.ethernetextender.com/ethe...xtension-kits/

Power over Ethernet runs 48V (like a telephone, but more current) down the
cable to power remote devices. The availability of commercial hardware means
it could be useful for home surveillance and alternate energy systems,
though noncompliant devices could be damaged if you don't observe the rather
complex standards. I worked on its R&D.
http://en.wikipedia.org/wiki/Power_over_Ethernet

jsw